Method of grinding bearing races



' Oct.4, 1932. K. HERRMANN 1,880,347

METHOD OF GRINDING BEARING RACES Filed Sept. 8. 1951 ATTO EYS.

INVENTOR.

dwj /mme Patented Oct. 4, 1932- UNITED STATES PATENT OFFICE KARL L. HERRMANN, OF SOU'IH .BEND, INDIANA, ASSIGNOR TO THE IBANTAM BALL BEARING COMPANY, OF SOUTH, BEND, INDIANA, A CORPORATION OF INDIANA METHOD OF GRINDING BEARING RACES Application filed September 8, 1981. Serial No. 561,599.

This invention relates to anti-friction bearings and particularly to the grinding of the race-ways for the anti-friction members forming a part of the bearing assembly.

The principal object of the invention is to provide means for securing the race member to be ground on a grinding machine in a man. ner so that the race member will have equal expansion or contraction over its entire area during the grinding o eration.

A further object is provide attaching means for a race member to be ground whereby the race member can be ground on its inner or outer cylindrical faces, consecutively, or both faces may be ground simultaneously without distorting the race member.

A further object is to provide lugs attached to the side face of a race member to be ground so that the inner and outer cylindrical faces of the ring are entirely exposed, the portions of the lugs to be attached tothe grinding machine being spaced from the race member to permit the grinding of the full cylindrical inner and outer faces of the race member at one operation if desired.

Heretofore it has been'the practice to se cure race members for anti-friction bearings against the face of a head plate of a grinding machine, clamps being used which gripped either the outer or inner cylindrical face of the race member so that the race member was clamped to the head plate in substantially the same manner as materials are held in the chuck of a lathe. This method has been found to be very unsatisfactory-because in securing the clamps on the race member securely enough to hold the same in position to be ground, the race member would become distorted to the extent that when the grinding operation was finished, either on the outer or inner cylindrical face thereof, it was found that the race member was out of round several thousandths of an inch. Heretofore it has been the practice to attach the race member to the head plate of a'grinding machine by the lugs heretofore described by clamping the same by its inner cylindrical face to permit grinding of the outer face and then clamping the race member at its outer face to permit grinding of its inner face, or vice versa. This required two operations and in setting up i the work on the grinding machine, it was found impossible to so center the work that i 'faces'that were concentric.

Applicant has found that by attaching lugs to the side face of the ring and then attaching the lugs on the face plate of the grinding machine, the inner and outer faces of the ring can, if desired, be ground simultaneously or if desired the inner cylindrical or the outer cylindrical face can be ground after which the other face is ground. By this method of attachment, the cylindrical surface of the ring is entirely exposed and is free to contract and expand durin the grinding operation so that when the grin ing of the race member is completed, the inaccuracies have been eliminated and the inner and outer faces are concentric thereby providing a race member which has longer life and which will not cause breakage of the anti-friction members due to the inaccuracies which have heretofore been present. In order that the invention may be better understood, reference may be had to the .accompanying drawing in which like numbers refer to like parts throughout the several views.

In the drawing, Figure 1 represents the side elevation of a grinding machine with the race member at tached to the head plate.

Figure 2 is an enlarged fragmentary see- I carrying a head plate 14 adapted to be rotated by any suitable power means which may be apulley 15 driven by a belt 16 from the power line, not shown.

The tail stock 17 may be moved longitudinally of the grinding machine to and from the work to be finished by means of the operating handle 18. The tail stock 17 carries a rotatable spindle 19 to which a grinding wheel 20 is preferably attached at the outer end, the spindle 19 being adapted to be rotated by any suitable source of power which may include the pulley 21 driven by the belt 22 from a power line, not illustrated. The grinding machine as described may be of conventional design and may be one of the well-known makes now on the market so that further description of the same is believed to be unnecessary.

The head plate 14 is preferably provided with ways 23 receiving the clamps 24 of conventional design and adapted to provide attaching means for the work to be ground.

The invention is particularly adaptable for race members for anti-friction bearings which are of large diameter and in which the thickness of the race member is of small cross sec tional area relative to the diameter of the same, as such members distort easily and take a set which is not a true cylinder.

In Figure 2, I have illustrated a race member 25 having concentric inner and outer cylindrical faces to the side face of which are attached lugs, each having a projecting portion 26 preferably soldered at 27 to the race member 25. Although I have found it preferable to solder the portions 26 of the lugs to the race member 25, if desired the same can be welded or otherwise attached thereto. The portions 26 of the lugs are preferably of less thickness than the finished thickness of the race member to be ground for a purpose to be hereafter described. The lugs also have attaching portions 28 substantially perpendicular to the-portions 26, the former being provided with slots 29 to receive the bolts 30 forming a part of the clamps 24. p 7

After the lugs are soldered on the side face of the race member 25, they are attached to the clamps on the head member in the usual manner whereby the race member is centered on the head member 14, to permit rotation of thesame about the common axis. The tail stock is then moved toward the race member and the grinding wheel moved into engagement with the inner face of the race member andthe grinding operation is made in the usual wa If desired, the tail stock may have a dou le spindle to carry a second grinding wheel 31 which may be moved into engagement with the, outer cylindrical face of the race member simultaneously with the grinding wheel 20 so that both the inner and outer cylindrical faces of the race member maybe ground at the same time. As the portions 28 of the lugs are spaced from the edge of the race members, the grinding wheels may ybe moved across either the inner or outer faces of the race member to. complete" the full grinding operation without inter- 5 fering withthe supporting means.

By supporting the race members in the manner described above, no pressure is applied to either the outer or inner face of the race member to distort the same and the race member, therefore, may be ground without encountering the usual distortion heretofore experienced so that when the grinding work is completed the inner and outer cylindrical is not limited to the form shown as it has been found that the attaching means comprising this invention may be used on a great variety of race members. I, therefore, wish to claim my invention broadly as well as specifically as indicated by the appended claims, the drawing and description being for the purpose of illustration only and not as limiting the scope of my invention.

What I claim I. In a grinding machine for finishing a bearing ring, supporting means for a ring to be ground on one of its cylindrical faces comprising, a plurality of lugs attached to one side face of said ring whereby the inner and outer cylindrical faces of said ring are spaced fromthe head plate of said machine and are entirely exposed during the grinding operation.

2. In a grinding machine for finishing a bearing ring, supporting means for a ring to be ground on one of its cylindrical faces comprising, a plurality of lugs, eachhavin a portion attached toone side face of said rlng and having a portion substantially perpendicular to said first portion providing attaching means whereby said ring is spaced from the head plate of said machine during the grinding operation.

3. In a grinding machine v for finishing a bearing ring, supporting means for a. ringto be ground on one of its cylindrical faces comprising, a plurality of lugs each having a portion of less thickness than the thickness of the :ring attached to one side face of said ring and having a portion extending substantially perpendicular to said first portion providing an, attaching means for said ring, whereby said ring is spaced from the head plate of said machine during the grinding operation.

4. In agrinding, machine for finishing a bearing ring, supporting means for a race memberfor an'anti-friction bearing to be ground comprising,a plurality of lugs soldered to one side face of saidrace member whereby the inner and outer cylindrical faces of said ring are spaced from the head plate of said machine and are entirely exposed to permit grinding of either or both of said faces at one operation.

5. In a grinding machine for finishing a bearing ring, supporting means for a race member for an anti-friction bearing to be ground, comprising supporting lugs attached to one side face of said race member and to the head plate of said machine to space said member therefrom to permit even expansion and extraction of said member during the grinding operation.

6. The method of grinding one of the cylindrical faces of a ring comprising, the attaching of lugs to one side face of said ring, securing the lugs on a face plate of a grinding machine, and grinding the entire cylindrical face of said ring at one operation.

7. The method of grinding the cylindrical faces of a ring comprising, attaching a plurality of lugs to one side face of said ring, securing the lugs to the face plate of a grinding machine, and grinding the entire inner and outer cylindrical faces of said ring simultaneously by one operation.

8. The method of grinding a race member for an anti-friction bearing comprising, the attaching 0f lugs to one side face of said race member, securing said lugs to the face plate of a grinding machine, rotating said race member, and grinding the cylindrical face of said ring over its entire area beginning at the sides opposite said lugs and continuing to the side adjacent to said In Signed b me at South Bend, Indiana, this 3rd day of geptember, 1931.

KARL L. HERRMANN. 

